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Why Equinus Is The Root Of All Foot Evils

Equnius has been associated with 96.5 percent of all biomechanically-related lower extremity pathologies.1 I have compiled a list of lower extremity pathologies (see below) that research has shown to have an equinus component along with the associated references.

Lower extremity orthopedic pathologies related to equinus:

Plantar heel pain/plantar fasciitis1-26

Achilles tendonitis/tendonosis1,27-33

Posterior tibial tendon dysfunction/adult flatfoot deformity2,8,25,26,32,34-42

Muscle strains43

Stress fractures31,44,45

Shin splints/medial tibial stress syndrome31,44,46,47

Iliotibial band syndrome44,46

Patellofemoral syndrome48

Ankle sprains/fractures49

Diabetic foot ulcers25,26,50-56

Charcot deformity55,57-60


Metatarsophalangeal synovitis/pre-dislocation syndrome8

Hallux abducto valgus1,2,25,36,40,61-63

Hammertoes/claw toes25,40,64

Lisfranc/midfoot arthrosis25,41,65

Hallux limitus/hallux rigidus7,40

Forefoot calluses1,40

Morton’s neuroma25,60,67

Chronic ankle instability68

Poor balance/increased fall rate in elderly69

Sever’s disease70,71

Pediatric flatfoot72,73

Lateral foot pain1

Genu recurvatum60

Low back pain60

Arch pain4

Ankle arthrosis25,26

Subtalar arthrosis25


Disclaimer: I am the inventor of the EQ/IQ equinus brace. To learn more about this device, please visit .


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8. Stotler WM, Van Bergeyk A, Manoli A. Preliminary results of gastrocnemius recession in adults with nonspastic equinus contracture. Presented at American Orthopaedic Foot and Ankle Society 18th Annual Summer Meeting, Traverse City, Mich., 2002.

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29. Gurdezi S, Kohls-Gatzoulis J, Solan MC. Results of proximal medial gastrocnemius release for Achilles tendinopathy. Foot Ankle Int. 2013; 34(10):1364-1369.

30. Kaufman KR, Brodine SK, Shaffer RA, et al. The effect of foot structure and range of motion on musculoskeletal overuse injuries. Am J Sports Med. 1999; 27(5):585–593.

31. Wilder RP, Sethi S. Overuse injuries: tendinopathies, stress fractures, compartment syndrome, and shin splints. Clin Sports Med. 2004; 23(1):55–81.

32. Lamm BM, Paley D, Herzenberg JE. Gastrocnemius soleus recession: a simpler, more limited approach. J Am Podiatr Med Assoc. 2005;95(1):18–25.

33. Kiewiet NJ, Holthusen SM, Bohay DR, Anderson JG. Gastrocnemius recession for chronic noninsertional Achilles tendinopathy. Foot Ankle Int. 2013; 34(4):481-5.

34. Alvarez RG, Marini A, Schmitt C, Saltzman CL. Stage I and II posterior tibial tendon dysfunction treated by a structured nonoperative management protocol: an orthosis and exercise program. Foot Ankle Int. 2006; 27(1):2-8.

35. Aronow MS. Triceps surae contractures associated with posterior tibial tendon dysfunction. Techniques Orthopaedics. 2000; 15(3):164-173.

36. Downey MS, Banks AS. Gastrocnemius recession in the treatment of nonspastic ankle equinus: a retrospective study. J Am Podiatr Med Assoc. 1989; 79(4):159–174.

37. Harris RI, Beath T. Hypermobile flatfoot with short tendo Achilles. J Bone Joint Surg. 1948; 30(1):116–141.

38. Hibbs RA. Muscle bound feet. NY Med J. 1914; 17(3):797–799.

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40. Sgarlato TE, Morgan J, Shane HS, Frenkenberg A. Tendo Achilles lengthening and its effect on foot disorders. J Am Podiatr Med Assoc. 1975; 65(9):849–871.

41. Hansen ST Jr. Functional Reconstruction of the Foot and Ankle, Lippincott Williams & Wilkins, Philadelphia, 2000.

42. Subotnick SI. Equinus deformity as it affects the forefoot. J Am Podiatry Assoc. 1971; 61(11):423–427.

43. Ekstrand J, Gillquist J. The frequency of muscle tightness and injuries in soccer players. Am J Sports Med. 1982; 10(1):75–78.

44. Neely FG. Biomechanical risk factors for exercise-related lower limb injuries. Sports Med. 1998; 26(6):395–413.

45. Fredericson M. Common injuries in runners. Diagnosis, rehabilitation and prevention. Sports Med. 1996;21(1):49-72.

46. Messier SP, Pittala KA. Etiologic factors associated with selected running injuries. Med Sci Sports Exerc. 1988; 20(5):501–505.

47. Lilletvedt J, Kreighbaum E, Phillips RL. Analysis of selected alignment of the lower extremity related to the shin splint syndrome. J Am Podiatry Assoc. 1979; 69(3):211-217.

48. Lun V, Meeuwisse WH, Stergiou P, Stefanyshyn D. Relation between running injury and static lower limb alignment in recreational runners. Brit J Sports Med. 2004; 38(5):576–580.

49. Tabrizi P, McIntyre WM, Quesnel MB, Howard, AW. Limited dorsiflexion predisposes to injuries of the ankle in children. J Bone Joint Surg. 2000; 82(2):1103–1106.

50. Armstrong DG, Stacpoole-Shea S, Nguyen H, Harkness LB. Lengthening of the Achilles tendon in diabetic patients who are at high risk for ulceration of the foot. J Bone Joint Surg. 1999; 81(4):535–538.

51. Barry DC, Sabacinski KA, Habershaw GM, et al. Tendo Achilles procedures for chronic ulcerations with transmetatarsal amputations. J Am Podiatr Med Assoc. 1993; 83(2):96–100.

52. Lin SS, Lee TH, Wapner, KL. Plantar forefoot ulceration with equinus deformity of the ankle in diabetic patients: The effect of tendo-Achilles lengthening and total contact casting. Orthopedics. 1996; 19(5):465–475.

53. Mueller MJ, Sinacore DR, Hastings MK, et al. Effect of Achilles tendon lengthening on neuropathic plantar ulcers. A randomized clinical trial. J Bone Joint Surg. 2003; 85-A(8):1436–1445.

54. Nishimoto GS, Attinger CE, Cooper PS. Lengthening the Achilles tendon for the treatment of diabetic plantar forefoot ulceration. Surg Clin North Am. 2003; 83(3):707–726.

55. Grant WP, Sullivan R, Sonenshine DE, et al. Electron microscopic investigation of the effects of diabetes mellitus on the Achilles tendon. J Foot Ankle Surg. 1997; 36(4):272–278, discussion 330.

56. Lavery LA, Armstrong DG, Boulton AJ. Ankle equinus deformity and its relationship to high plantar pressure in a large population with 
diabetes mellitus. J Am Podiatr Med Assoc. 2002; 92(9):479–482.

57. Early JS, Hansen ST. Surgical reconstruction of the diabetic foot: a salvage approach for midfoot collapse. Foot Ankle Int. 1996; 17(6):325–330.

58. Schon LC, Easley ME, Weinfeld SB. Charcot neuroarthropathy of the foot and ankle. Clin Orthop. 1998; 349:116–131.

59. Banks AS, McGlamry ED. Charcot foot. J Am Podiatr Med Assoc. 1989; 79(5):213–235.

60. Downey MS. Ankle Equinus. In Banks AS, Downey MS, Martin DE, Miller SJ (eds.) McGlamry’s Comprehensive Textbook of Foot and Ankle Surgery, Lippincott Williams & Wilkins, Philadelphia, 2001, pp. 715–760.

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62. Holstein A. Hallux valgus—an acquired deformity of the foot in cerebral palsy. Foot Ankle Int. 1980; 1(1):33-38.

63. Barouk LS. The effect of gastrocnemius tightness on the pathogenesis of juvenile hallux valgus: a preliminary study. Foot Ankle Clin. 2014; 19(4):807-822.

64. Green DR, Ruch JA, McGlamry ED. Correction of equinus-related fore- foot deformities: a case report. J Am Podiatry Assoc. 1976; 66(10):768–780.

65. Nemec SA, Habbu RA, Anderson JG, Bohay DR. Outcomes following midfoot arthrodesis for primary arthritis. Foot Ankle Int. 2011; 32(4):355-361.

66. Maceira E, Monteagudo M. Functional hallux rigidus and the Achilles-calcaneus-plantar system. Foot Ankle Clin. 2014; 19(4):669-699.

67. Root ML, Orien WP, Weed JH. Forces acting upon the foot during locomotion: abnormal motion of the foot. In Normal and Abnormal Function of the Foot, Clinical Biomechanics, Vol 2, Clinical Biomechanics Corp., Los Angeles, 1977, pp. 165–179, 295.

68. Pope R, Herbert R, Kirwan J. Effects of ankle dorsiflexion range and pre-exercise calf muscle stretching on injury risk in Army recruits. Aust J Physiother. 1998;44(3):165-172.

69. Gajdosik RL, Vander Linden DW, McNair PJ, et al. Effects of an eight-week stretching program on the passive-elastic properties and function of the calf muscles of older women. Clin Biomech (Bristol, Avon). 2005, 20(9):973–983.

70. Becerro de Bengoa Vallejo R, Losa Iglesias ME, Rodríguez Sanz D, et al. Plantar pressures in children with and without Sever’s disease. J Am Podiatr Med Assoc. 2011; 101(1):17-24.

71. Szames SE, Forman WM, Oster J, et al. Sever's disease and its relationship to equinus: a statistical analysis. Clin Podiatr Med Surg. 1990; 7(2):377-384.

72. Reimers J, Pedersen B, Brodersen A. Foot deformity and the length of the triceps surae in Danish children between 3 and 17 years old. J Pediatr Orthop B. 1995; 4(1):71-73.

73. DiGiovanni CW, Langer P. The role of isolated gastrocnemius and combined Achilles contractures in the flatfoot. Foot Ankle Clin. 2007; 12(2):363-379.

Additional References

74. Lundgren P, Nester C, Liu A, et al. Invasive in vivo measurement of rear-, mid-and forefoot motion during walking. Gait Posture. 2008; 28(1):93-100.

75. Evans AM, Scutter SD. Sagittal plane range of motion of the pediatric ankle joint: a reliability study. J Am Podiatr Med Assoc. 2006; 96(5):418-422.

76. Gourdine-Shaw MC, Lamm BM, Herzenberg JE, Bhave A. Equinus deformity in the pediatric patient: Causes, evaluation, and management. Clin Podiatr Med Surg. 2010; 27(1):25-42.



Patrick, Nice reference list! There should be no doubt that equinus is the most under diagnosed and under treated conditions in the lower extremity. Nice job.
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